Do unicode URLs actually provide any real value? Every web user must be already used to typing Latin characters because so many major websites use them. So nobody would be excluded by that. Whereas, any non-Latin character is going to be nearly impossible for most of the world to enter. A particularly terrible language is Chinese where most old people can't type the characters even though they can type Latin letters.…
Is that your personal experience? Most input methods I know work by 1. knowing the Pinyin romanization of the word you want to type 2. typing it in 3. selecting the appropriate characters from a long list of candidates.
If they know the characters and Latin letters, then the only roadblock I can think of would be not knowing Pinyin. That shouldn't take weeks to learn if you already know Chinese, it's more like learning a very simple alphabet.